Interlocking Hollow Tanks

ABSTRACT

A set of interlocking tanks. The tanks have respective sidewalls including cooperating interlock features formed inclusive of the hollows of the tanks which are mutually correlated and reciprocally shaped so that the interlock feature of one tank interlocks with respect to the interlock feature of the other tank to thereby connect the tanks together as a single subassembly. The interlocking is selectively releasable.

TECHNICAL FIELD

The present invention relates to hollow tanks used for holding and dispensing of liquids, and more particularly to hollow tanks which are mutually configured to provide an interlocking relationship therebetween.

BACKGROUND OF THE INVENTION

Hollow tanks, containers and the like (hereinafter simply referred to as “tanks”) which are used for the holding liquids, are ubiquitous. Tanks used for automotive applications are singular constructions, each tank being a stand-alone subassembly, complete and solitary in its own right. These tanks are used, by way of example, for the holding a wide variety of liquids, for example: fuel, washer fluid, oil, coolant, and in the case of diesel engines, urea used in conjunction with the injection of diesel fuel with respect to the diesel engine of the motor vehicle.

In modern motor vehicles, component packaging space is at a premium, and this premium applies to each tank used on the motor vehicle. In some cases the tank has a sidewall to which is imparted geometrical shapes which allows for placement between surrounding components, as is frequently done for plastic washer fluid and overflow coolant tanks which are generally disposed in the engine compartment. However, in the case of fuel tanks which are disposed at the underbody of the motor vehicle, unique conditions thereat render packaging space at a high premium. For example, suspension and exhaust components crowd the underbody, and exhaust temperatures mandate the need for providing at least a required minimal amount of clearance, and even additional parts may be needed, such as for example heat shields.

A typical motor vehicle application of tanks is shown at FIG. 1, wherein a motor vehicle 10 (shown in part at the underbody thereof) has a diesel fuel tank 12 for holding therein diesel fuel and a generally adjacent urea tank 14 for holding therein urea for mixing with the diesel fuel, typically in conjunction with an injection process of the diesel engine of the motor vehicle. The diesel fuel tank 12 has its respective bracketing 16 for its attachment to the motor vehicle underbody 18, and the urea tank 14 has its respective bracketing 20 for its respective attachment to the underbody. Even though there may be a potential for shrinking the fuel tank due to mpg improvement, there is still crowding that cannot be overcome by conventional tank modalities.

Accordingly, there remains in the art the clear need for a fuel tanks underbody packaging efficiency improvement.

SUMMARY OF THE INVENTION

The present invention is a set of interlocking tanks, wherein the tanks have respective sidewalls including cooperating interlock features formed inclusive with the hollow of the tanks which are mutually correlated and reciprocally shaped so that the interlock feature of one tank interlocks with respect to the interlock feature of the other tank to thereby connect the tanks together as a single subassembly.

By way of exemplification, a first tank may have a first interlock feature of its respective sidewall in the form of a female concavity and a second tank may have a second interlock feature of its respective sidewall in the form of a male protuberance, wherein the female concavity and the male protuberance are reciprocally shaped so as to provide mutual interlocking by a mutual interference fit that prevents release, that is, “uninterlocking”, except for a relative movement in one of more predetermined directions (the same one or more directions that are also used for interlocking of the tanks), wherein the interlocking is, preferably, unidirectional. This unidirectional interlocking of the cooperating interlock features may be configured, for example, for interlocking/uninterlocking by relative movement of the tanks along, for example, a Z axis, but have an interlocking (interference fit) that prevents uninterlocking (release) in any direction parallel to a plane X-Y which is perpendicular to the Z axis. While a suitable shape to provide unidirectional interlocking is a mutually counterpart bulbous end portion of each of the female concavity and the male protuberance, any mutually cooperating shapes which generally provide this interlocking functionality are contemplated by the term “bulbous”.

One or more cooperating interlock features may be provided in association with two or more tanks. The interlock features unite the tanks, whereby packaging, shipping and final installation can be carried out as a single subassembly.

Accordingly, it is an object of the present invention to provide a set of interlocking tanks.

This and additional objects, features and advantages of the present invention will become clearer from the following specification of a preferred embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a motor vehicle underbody, showing a conventional diesel fuel tank and a companion urea tank therefor.

FIG. 2 is a plan view of a motor vehicle underbody, showing interlocking diesel fuel and urea tanks therefor according to the present invention.

FIG. 3A is a perspective view of a pair of interlocking fuel tanks according to the present invention, shown mutually separated.

FIG. 3B is a perspective view of the pair of interlocking tanks of FIG. 3A, now shown mutually interlocked.

FIG. 4A is a first example of a set of interlocking according to the present invention.

FIG. 4B is a second example of a set of interlocking tanks according to the present invention.

FIG. 4C is a third example of a set of interlocking tanks according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the Drawing, FIGS. 2 through 4C depict examples of a set of interlocking tanks 100 according to the present invention.

An example of a motor vehicle application for a set of interlocking tanks 100, 100 a according to the present invention is depicted at FIG. 2, wherein a diesel fuel tank 102 for holding within the hollow 102H thereof diesel fuel is interlocked with respect to its companion urea tank 104 for holding within the hollow 104H thereof urea. The diesel and urea tanks 102, 104 are shown disposed at the underbody 106 of a motor vehicle (shown in part) 108. The diesel fuel tank 102 has a sidewall 102 a defining the hollow 102H of the diesel fuel tank and the urea tank 104 has a sidewall 104 a defining the hollow 104H of the urea thank, wherein the sidewalls have cooperating interlock features 110 formed inclusive with the hollow of the tanks which are mutually correlated and reciprocally shaped so that a first interlock feature 110 a of the diesel fuel tank 102 interferingly locks with respect to a second interlock feature 110 b of the urea tank 104.

It will be seen at FIG. 2 that the set of interlocking tanks 100 a advantageously provides nesting of the diesel fuel tank 102 with respect to the urea tank 104, wherein because the tanks are mutually interlocked by the cooperating interlock features 110 into a single subassembly 112, the bracketing 114 with respect to the underbody 106 of the motor vehicle 108 is common to the set of interlocking tanks 100 a and that since the tanks are abut and adjoin, the space occupied by the tanks subassembly is at a minimum. Further, in operation during cold conditions, when the diesel fuel in the diesel fuel tank 102 heats (via returning fuel), the abutting relation of the urea tank 104 will benefit the urea due to heat transfer thereto from the diesel fuel tank.

In contrast to the adjacent but separate tanks 12, 14 that form two separate subassemblies of FIG. 1, single subassembly 112 provided by the set of interlocking tanks 100 a shown at FIG. 2 provides both a far superior space utilization, as well as ability to pre-assemble the diesel fuel tank 102 and the urea tank 104 into the single subassembly 112 (not possible conventionally) by the interlocking of the cooperating interlock features 110, shipping the subassembly as a united unit, and then installing the subassembly on the motor vehicle 108 into the same packaging bay of the underbody 106.

Turning attention now to FIGS. 3A and 3B, a methodology for interlocking/uninterlocking of the set of interlocking tanks 100 a will be described, merely by way of illustrative example.

The diesel fuel tank 102 has a first interlock feature 110 a of its respective sidewall 102 a in the form of a female concavity 116 and the urea tank 104 has a second interlock feature 110 b of its respective sidewall 104 a in the form of a male protuberance 118, wherein since the diesel fuel and urea tanks are both preferably constructed of plastic, most preferably of a high density polyethylene, the sidewalls (and the cooperating interlock features) are formed by a suitable plastic forming process, such as blow molding. The female concavity 116 and the male protuberance 118 are reciprocally shaped so as to provide a mutual interlock therebetween (that is, a mutual interference fit) which is characterized by a unidirectional interlocking that prevents separation of the tanks 102, 104 except for a predetermined relative movement of the tanks. It is to be noted that either one of the diesel fuel and urea tanks may have one of the male protuberance or the female concavity, wherein the other of the diesel fuel and urea tanks would then have the other of the male protuberance or female concavity. The sidewall 102 a of the diesel fuel tank 102 also includes mating first walls 102 b. The sidewall 104 a of the urea tank 104 also includes mating second walls 104 b, wherein the mating first and second walls abut snuggly with each other, respectively.

As shown at FIG. 3A, the tanks are separated and positioned for unidirectional interlocking along a Z axis. The diesel fuel tank 102 and the urea tank 104 are moved relative to each other along the Z axis so that the male protuberance 118 inserts into the female concavity 116, as shown at FIG. 3B. Now, since the female concavity 116 has a female bulbous end portion 116 a and the male protuberance 118 has a counterpart male bulbous end portion 118 a which is shaped reciprocally to the shape of the female bulbous end portion, unlocking of the tanks 102, 104 is prevented in any direction parallel to a plane X-Y which is perpendicular to the Z axis. The diesel fuel and urea tanks 102, 104 may be selectively released from interlocking (that is, uninterlocked) by another movement along the Z axis.

The set of interlocking tanks 100 a used for diesel fuel and urea improves the efficiency of the packaging of the respective diesel fuel and urea tanks 102, 104 and allows greater fuel and urea volumes in the standard space, or permits the same fuel and urea volumes if a smaller space is needed. The set of interlocking tanks 110 a allows for improved efficiency and cost of vehicle assembly by reducing the overall number of subassemblies and installation fasteners. Further, since the diesel fuel tank 102 and the urea tank 104 are not bonded together and are selectively releasable from interlocking, either one of the tanks can be serviced or replaced independent of, and without affecting, the other tank.

Some additional advantages of the interlocking set of tanks 100 a include: reduced costs due to the elimination of duplication of mounting hardware and fasteners for each separate tank; reduced vehicle assembly labor time and cost due to the tanks being a single subassembly rather than two separate subassemblies; increased tank liquid holding volumes, due to packaging efficiency gains; elimination of tanks packaging space clearances therebetween, thereby saving overall packaging space volume required for given fuel and urea volumes and sharing of available heat between the tanks; and reduction of mass by elimination of separate mounting brackets and associated mounting hardware; and improved diesel fuel line 102L and urea line 104L routing (see FIG. 2) by allowing these lines be bundled together and routed together through the vehicle rather than routed separately (see for example lines 12L and 14L of FIG. 1).

FIGS. 4A through 4C depict various exemplifications of sets of interlocking tanks 100.

At FIG. 4A, a most preferred example of a set of interlocking tanks 100, 100 b is shown, wherein a first tank 140 is interlocked with respect to a (relatively smaller) second tank 142 via cooperating interlock features 144 generally as described hereinabove. The first tank 140 has a sidewall 140 a including a first interlock feature 146, mating first walls 140 b and a mating floor 140 c, wherein the mating first walls and mating floor cooperate to form a tank seat 150. The second tank 142 has a sidewall 142 a including a second interlock feature 152, mating second walls 142 b and a mating bottom 142 c, wherein the mating walls and mating bottom cooperate to fit snuggly into the tank seat 150.

In operation of the set of interlocking tanks 100 b, the first and second tanks 140, 142 are positioned relative to each other for unidirectional interlocking, and then moved relative to each other along the negative Z′ axis (see arrow A_(ZN)) so that the second interlock feature 152 inserts into the first interlock feature 146. Now, unlocking of the first and second tanks 140, 142 is prevented in any direction parallel to a plane X′-Y′ which is perpendicular to the Z′ axis, as well as in the negative Z′ axis (see arrow A_(ZN)). The first and second tanks 140, 142 may be selectively released from interlocking (uninterlocked) by an opposite movement along the positive Z′ axis (see arrow A_(ZP)).

At FIG. 4B, an example of a set of interlocking tanks 100, 100 c is shown, similar to the first and second tanks of FIG. 4A, except now the first and second tanks 160, 162 have first and second cooperating interlock features 164, 166.

In operation of the set of interlocking tanks 100 c, the first and second tanks 160, 162 are positioned relative to each other for unidirectional interlocking, and then moved relative to each other along the negative Z″ axis (see arrow AA_(ZN)) so that the first interlock feature 164 a of the first cooperating interlock features 164 inserts into the second interlock feature 164 b of the first cooperating interlock features 164, and the first interlock feature 166 a of the second cooperating interlock features 166 inserts into the second interlock feature 166 b of the second cooperating interlock features 166. Now, unlocking of the first and second tanks 160, 162 is prevented in any direction parallel to a plane X″-Y″ which is perpendicular to the Z″ axis, as well as in the negative Z″ axis (see arrow AA_(ZN)). The first and second tanks 160, 162 may be selectively released from interlocking (uninterlocked) by an opposite movement along the positive Z″ axis (see arrow AA_(ZP)).

At FIG. 4C, another example of a set of interlocking tanks 100, 100 d is shown, wherein now three tanks are interlocked: a first tank 180 is interlocked with respect to a (relatively smaller) second tank 182 via first cooperating interlock features 184 generally as described hereinabove and a (relatively smaller) third tank 186 via second cooperating interlock features 188 generally as described hereinabove.

In operation of the set of interlocking tanks 100 d, the first and second tanks 180, 182 are positioned relative to each other for unidirectional interlocking, and then moved relative to each other along the Z″′ axis so that the first interlock feature 184 a inserts into the second interlock feature 184 b of the first cooperating interlock features 184. Now, unlocking of the first and second tanks 180, 182 is prevented in any direction parallel to a plane X″′-Y″′ which is perpendicular to the Z″′ axis. The first and second tanks 180, 182 may be selectively released from interlocking (uninterlocked) by another movement along the Z″′ axis.

In further operation of the set of interlocking tanks 100 d, the first and third tanks 180, 186 are positioned relative to each other for unidirectional interlocking, and then moved relative to each other along the Z″′ axis so that the first interlock feature 188 a inserts into the second interlock feature 188 b of the second cooperating interlock features 188. Now, unlocking of the first and third tanks 180, 186 is prevented in any direction parallel to an plane X″′-Y″′ which is perpendicular to the Z″′ axis. The first and third tanks 180, 186 may be selectively released from interlocking (uninterlocked) by another movement along the Z″′ axis.

To those skilled in the art to which this invention appertains, the above described preferred embodiment may be subject to change or modification. Such change or modification can be carried out without departing from the scope of the invention, which is intended to be limited only by the scope of the appended claims. 

1. A set of interlocking tanks, comprising: a first tank having a first tank sidewall defining a first tank hollow; a second tank having a second tank sidewall defining a second tank hollow; and cooperating interlock features disposed at said first tank sidewall and said second tank sidewall and formed inclusive with the first tank hollow and the second tank hollow; wherein said cooperating interlock features selectively interlock to thereby interlock said first and second tanks.
 2. The set of interlocking tanks of claim 1, wherein said cooperating interlock features comprise: a first interlock feature disposed at said first tank sidewall; and a second interlock feature disposed at said second tank sidewall; wherein said first and second interlock features mutually cooperate to provide said interlock of said first and second tanks.
 3. The set of interlocking tanks of claim 2, wherein said interlock of said first and second tanks is selectively releasable.
 4. The set of interlocking tanks of claim 3, wherein said cooperating interlock features further comprise: said first interlock feature comprising a female concavity formed of said first tank sidewall; and said second interlock feature comprising a male protuberance formed of said second tank sidewall; wherein said female concavity and said male protuberance are reciprocally shaped to provide said interlock of said first and second tanks when said male protuberance is disposed in said female concavity.
 5. The set of interlocking tanks of claim 4, wherein said cooperating interlock features further comprise said reciprocal shape of said female concavity and said male protuberance is such that said interlocking of said first and second tanks is unidirectional.
 6. The set of interlocking tanks of claim 5, wherein said unidirectional interlocking of said first and second tanks comprises interlocking and uninterlocking said first and second tanks by relative movement of said first and second tanks along a Z axis, wherein said first and second tanks are interlocked by an interference fit of said male protuberance with respect to said female concavity in any direction parallel to a plane X-Y which is perpendicular to the Z axis.
 7. The set of interlocking tanks of claim 3, further comprising: said first tank sidewall having a first tank mating wall; and said second tank sidewall having a second tank mating wall; wherein when said first and second tanks are interlocked by said cooperating interlock features, said first tank mating wall abuttingly adjoins said second tank mating wall.
 8. The set of interlocking tanks of claim 7, wherein said cooperating interlock features further comprise: said first interlock feature comprising a female concavity formed of said first tank sidewall; and said second interlock feature comprising a male protuberance formed of said second tank sidewall; wherein said female concavity and said male protuberance are reciprocally shaped to provide said interlock of said first and second tanks when said male protuberance is disposed in said female concavity.
 9. The set of interlocking tanks of claim 8, wherein said cooperating interlock features further comprise said reciprocal shape of said female concavity and said male protuberance is such that said interlocking of said first and second tanks is unidirectional.
 10. The set of interlocking tanks of claim 9, wherein said unidirectional interlocking of said first and second tanks comprises interlocking and uninterlocking said first and second tanks by relative movement of said first and second tanks along a Z axis, wherein said first and second tanks are interlocked by an interference fit of said male protuberance with respect to said female concavity in any direction parallel to a plane X-Y which is perpendicular to the Z axis.
 11. The set of interlocking tanks of claim 7, further comprising: said first tank sidewall having a first tank floor; and said second tank sidewall having a second tank bottom; wherein when said first and second tanks are interlocked by said cooperating interlock features, said second tank bottom abuttingly adjoins and rests upon said first tank floor.
 12. The set of interlocking tanks of claim 11, wherein said cooperating interlock features further comprise: said first interlock feature comprising a female concavity formed of one of said first tank sidewall and said tank sidewall; and said second interlock feature comprising a male protuberance formed of the other of said first tank sidewall and said second tank sidewall; wherein said female concavity and said male protuberance are reciprocally shaped to provide said interlock of said first and second tanks when said male protuberance is disposed in said female concavity.
 13. The set of interlocking tanks of claim 12, wherein said cooperating interlock features further comprise said reciprocal shape of said female concavity and said male protuberance is such that said interlocking of said first and second tanks is unidirectional.
 14. The set of interlocking tanks of claim 13, wherein said unidirectional interlocking of said first and second tanks comprises interlocking and uninterlocking said first and second tanks by relative movement of said first and second tanks along a Z axis, wherein said first and second tanks are interlocked by an interference fit of said male protuberance with respect to said female concavity in any direction parallel to a plane X-Y which is perpendicular to the Z axis.
 15. The set of interlocking tanks of claim 1, wherein said cooperating interlock features comprise: a first interlock feature disposed at said first tank sidewall; a second interlock feature disposed at said first tank sidewall; a third interlock feature disposed at said second tank sidewall; and a fourth interlock feature disposed at said second tank sidewall; wherein said first and third interlock features mutually cooperate and said second and fourth interlock features mutually cooperate to thereby collectively provide said interlock of said first and second tanks; and wherein said interlock of said first and second tanks is selectively releasable.
 16. A set of interlocking tanks, comprising: a diesel fuel tank having a diesel fuel tank sidewall defining a diesel fuel tank hollow; a urea tank having a urea tank sidewall defining a urea tank hollow; and cooperating interlock features disposed at said diesel fuel tank sidewall and said urea tank sidewall formed inclusive of the diesel fuel tank hollow and the urea tank hollow; wherein said cooperating interlock features selectively interlock to thereby interlock said diesel fuel and urea tanks as a single subassembly.
 17. The set of interlocking tanks of claim 16, wherein said cooperating interlock features comprise: a first interlock feature disposed at said diesel fuel tank sidewall; and a second interlock feature disposed at said urea tank sidewall; wherein said first and second interlock features mutually cooperate to provide said interlock of said diesel fuel and urea tanks; and wherein said interlock of said diesel fuel and urea tanks is selectively releasable.
 18. The set of interlocking tanks of claim 17, wherein said cooperating interlock features further comprise: said first interlock feature comprising a female concavity formed of one of said diesel fuel tank sidewall and urea tank sidewall; and said second interlock feature comprising a male protuberance formed of the other of said diesel fuel tank sidewall and said urea tank sidewall; wherein said female concavity and said male protuberance are reciprocally shaped to provide said interlock of said diesel fuel and urea tanks when said male protuberance is disposed in said female concavity.
 19. The set of interlocking tanks of claim 18, wherein said cooperating interlock features further comprise said reciprocal shape of said female concavity and said male protuberance being such that said interlocking of said diesel fuel and urea tanks is unidirectional; and wherein said unidirectional interlocking of said diesel fuel and urea tanks comprises interlocking and uninterlocking said diesel fuel and urea tanks by relative movement of said diesel fuel and urea tanks along a Z axis, wherein said diesel fuel and urea tanks are interlocked by an interference fit of said male protuberance with respect to said female concavity in any direction parallel to a plane X-Y which is perpendicular to the Z axis.
 20. The set of interlocking tanks of claim 19, further comprising: said diesel fuel tank sidewall having a diesel fuel tank mating wall and a diesel fuel tank floor; and said urea tank sidewall having a urea tank mating wall and a urea tank bottom; wherein when said diesel fuel and urea tanks are interlocked by said cooperating interlock features, said diesel fuel tank mating wall abuttingly adjoins said urea tank mating wall and urea tank bottom abuttingly adjoins and rests upon said diesel fuel tank floor. 